[115]Playwright中上下文管理new

[115]Playwright中上下文管理new

1. 什么是浏览器上下文？

相当于打开了一个浏览器，通过_context() 创建一个新的浏览器上下文。它不会与其他浏览器上下文共享 cookies/缓存。使用_context() 创建context对象，context之间是相互隔离的，可以理解为轻量级的浏览器实例。 在浏览器中有很多的标签页，这种都是通过浏览器上下文进行管理的，通过context = _context() 创建一个浏览器上下文，然后通过上下问，可以创建出很多个标签页来，如：page1 = _page()，page2 = _page()

代码语言：javascript代码运行次数：0运行复制

from playwright.sync_api import sync_playwright

with sync_playwright() as playwright:
    browser = launch(headless=False)
    context = _context()
    page1 = _page()
    page1.goto('')
    page1.wait_for_timeout(2000)
    page2 = _page()
    page2.goto('')
    page2.wait_for_timeout(2000)
    ()
    ()

2. 浏览器上下文的使用

2.1 新标签页

创建上下文管理器，打开百度网站，点击新闻页面，通过_page()获取新标签页的对象，最后分别打印出百度首页的标题和百度新闻页的标题

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from playwright.sync_api import sync_playwright

with sync_playwright() as playwright:
    browser = launch(headless=False)
    context = _context()
    page = _page()
    page.goto("/")
    print(())
    with _page() as new_page_info:
        ('text=新闻')
    new_page = new_page_info.value
    # 等待页面加载到指定状态
    new_page.wait_for_load_state()
    print(new_())
    new_() # 关闭新打开的标签页 

# 百度一下，你就知道
# 百度新闻——海量中文资讯平台

同样的，使用这种方式获取新的标签页也是可以的

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with _popup() as new_page_info:
    ('text=新闻')
new_page = new_page_info.value # 获取新页面的上下文
new_page.wait_for_load_state()  # 等待页面加载完成

url=new_page.url # 获取新打开页面的url
new_() # 关闭新打开的标签页 

2.2 保存cookie到本地

方式一： 通过context上下文获取cookies，然后通过json模块写入文件

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from playwright.sync_api import sync_playwright
import json

with sync_playwright() as playwright:
    browser = launch(headless=False)
    context = _context()
    page = _page()
    page.goto("/")
    # 获取cookie信息
    cookies = ()
    with open("cookie.json", "w") as f:
        json.dump(cookies, f, indent=4)
    ()

方式二： 直接使用context.storage_state()指定下文件目录写入文件

代码语言：javascript代码运行次数：0运行复制

from playwright.sync_api import sync_playwright

with sync_playwright() as playwright:
    browser = launch(headless=False)
    context = _context()
    page = _page()
    page.goto("/")
    context.storage_state(path="cookie.json")
    ()
    ()

2. 加载cookies

在创建上下文管理器的时候，可以通过加载本地之前保存的cookie来完成免登录的操作

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from playwright.sync_api import sync_playwright

with sync_playwright() as playwright:
    browser = launch(headless=False)
    # 创建上下文时，加载本地cookie.json
    context = _context(storage_state="cookie.json")
    page = _page()
    page.goto("/")
    ()
    ()

同样的，还可以使用老办法进行获取cookie，然后通过上下文来加载cookie

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# 加载本地cookie信息
with open('cookies.json', 'r', encoding='utf-8') as f:
    cookies = json.load(f)
    # 通过上下文进行添加cookie
    context.add_cookies(cookies)

2.4 加载基础路径

对于单页面应用，可以通过创建上下文时候加载基础路径来进行页面跳转

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from playwright.sync_api import sync_playwright

with sync_playwright() as playwright:
    browser = launch(headless=False)
    context = _context(base_url='/')
    page = _page()
    # 打开首页
    page.goto("/")
    print(())
    page.wait_for_timeout(2000)
    # 打开文章详情页
    page.goto('/#/article/7')
    print(())
    page.wait_for_timeout(2000)
    ()
    ()

2.5 获取网页源码

通过()获取网页完整源码

代码语言：javascript代码运行次数：0运行复制

from playwright.sync_api import sync_playwright

with sync_playwright() as playwright:
    browser = launch(headless=False)
    context = _context()
    page = _page()
    page.goto("/")
    print(())
    ()
    ()

同时还有以下两种方式：

• inner_html()：获取元素的整个html源码内容
• inner_text()：获取元素的文本内容，会格式化进行显示
• text_content()：用来获取某个元素内所有文本内容，包含子元素内容，隐藏元素也能获取

代码语言：javascript代码运行次数：0运行复制

from playwright.sync_api import sync_playwright

with sync_playwright() as playwright:
    browser = launch(headless=False)
    context = _context()
    page = _page()
    page.goto(";)
    # 获取某个元素的HTML
    info = page.locator('.user-profile-head-info-r-c')
    print(info.inner_html())
    print(info.inner_text())
    print(_content())
    ()
    ()

参考：

本文参与 腾讯云自媒体同步曝光计划，分享自作者个人站点/博客。 原始发表：2024-12-20，如有侵权请联系 cloudcommunity@tencent 删除前往查看browserplaywright百度管理浏览器